Prosecutors say Hunter Stephenson was driving on Route 1 in Charlestown on the afternoon of Aug. 29 when his vehicle crossed the center median and struck a motorcycle head-on.

The motorcycle operator, 21-year-old Thomas Hug of Hopkinton, died as a result of the crash. His mother said he was getting ready to start his junior year at the University of Rhode Island.

According to Charlestown police, Stephenson was drinking with friends at a Westerly beach prior to the 4 p.m. crash.

“They were actually going to meet some other friends, those plans fell through, and they were going back to Westerly to pick up some other friends that were at the beach,” said Lt. Patrick McMahon of the Charlestown Police Department. “Unfortunately, he made a bad decision that day, and this is where we’re at.”

Stephenson, who turns 18 in December, is charged with DUI – death resulting, driving to endanger – death resulting, and possession of alcohol by a minor, along with numerous motor vehicle violations, including speeding.

Stephenson was arraigned Tuesday and released on $10,000 personal recognizance. Under the conditions of his bail, he isn’t allowed to drive and must undergo alcohol counseling.

Stephenson’s defense attorney John MacDonald declined to comment on the case.